ROS2 Commands Cheat Sheet

1. ROS 2 Commands Cheat Sheet
General Format of ROS 2 CLI:------
The keyword ‘ros2‘ is the unique entry
point for the CLI.
Every ROS 2 command starts with the
ros2 keyword, followed by a command,
a verb, and possibly positional/optional
arguments.
ros2 [command] [verb]
<positional-argument>
<optional-arguments>
For Help on ROS 2 CLI commands-
$ ros2 [command] --help
$ ros2 [command] [verb] -h
Action—-----------------------------------------
A type of message-based
communication that allows a client node
to request a specific goal to be
achieved by a server node, and receive
feedback and/or a result from the server
node once the goal has been
completed.
Command
ros2 action [verb] <arguments>
Verbs
list: identify all the actions in the
ROS graph
info <action_name>: introspect
about an action
send_goal <action_name>
<action_type> <values>: send an
action goal
Arguments
-f: echo feedback messages for the
goal
Examples
$ ros2 action list
$ ros2 action info
/turtle1/rotate_absolute
$ ros2 action send_goal
/turtle1/rotate_absolute
turtlesim/action/RotateAbsolute
"{theta: 1.57}"
$ ros2 interface show
turtlesim/action/RotateAbsolute
Bag—------------------------------—-----------
A file format used to record and
playback ROS 2 topics.
Command
ros2 bag [verb] <arguments>
Verbs
record <topic_name>: record the
data published to topic
info <bag_file_name>: get details
about bag file
play <bag_file_name>: replaying
the bag file
Arguments
--clock: publish to /clock at a specific
frequency in Hz
-l: enable loop playback when
playing a bag file
-r: rate to play back messages
-s: storage identifier to be used,
defaults to 'sqlite3'
--topics: topics to replay, separated
by space
--storage-config-file: path to a yaml
file defining storage specific
configurations
-a: recording all topics, required if no
topics are listed explicitly or through
a regex
-e: recording only topics matching
provided regular expression
-x: exclude topics matching provided
regular expression
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2. ROS 2 Commands Cheat Sheet
-o: destination of the bag file to
create
Examples
$ ros2 bag record /turtle1/cmd_vel
$ ros2 bag record -o my_bag
/turtle1/cmd_vel /turtle1/pose
$ ros2 bag info <bag_name.db3>
$ ros2 bag play <bag_name.db3>
Component—---------------------------------
A modular unit of software that
encapsulates functionality, data, and
communication.
**ROS 2 Components ≈ ROS 1
Nodelets
Command
ros2 component [verb]
<arguments>
Verbs
list: output a list of running
containers and components
load: load a component into a
container node
standalone: run a component into its
own standalone container node
types: output a list of components
registered in the ament index
unload: unload a component from a
container node
Arguments
-n: component node name
--node-namespace: component
node namespace
--log-level: component node log
level
-r: component node remapping rules,
in the 'from:=to' form
-p: component node parameters, in
the 'name:=value' form
Examples
$ ros2 component list
$ ros2 component types
$ ros2 component load
/ComponentManager composition
composition::Talker
Control—---------------------------------------
A control framework to simplify
integrating new hardware and
overcome some drawbacks.
Command
ros2 control [verb] <arguments>
Verbs
list_controller_types: output the
available controller types and their
base classes
list_controllers: output the list of
loaded controllers, their type, and
status
list_hardware_interfaces: output
the list of loaded controllers, their
type and status
load_controller: load a controller in
a controller manager
reload_controller_libraries: reload
controller libraries
set_controller_state: adjust the
state of the controller
switch_controllers: switch
controllers in a controller manager
unload_controller: unload a
controller in a controller manager
view_controller_chains: generates
a diagram of the loaded chained
controllers
Arguments
-c: name of the controller manager
ROS node
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3. ROS 2 Commands Cheat Sheet
--claimed-interfaces: list controller's
claimed interfaces
--required-state-interfaces: list
controller's required state interfaces
--required-command-interfaces: list
controller's required command
interfaces
Examples
$ ros2 control list_controllers
$ ros2 control
list_hardware_components -h
$ ros2 control
list_hardware_interfaces
Daemon—--------------------------------------
A system-level process that runs in the
background and provides various
services to ROS 2 nodes and
components.
**ROS 2 Daemon ≈ ROS 1 Master
Command
ros2 daemon [verb]
Verbs
start: start the daemon if it isn't
running
status: output the status of the
daemon
stop: stop the daemon if it is running
Examples
$ ros2 daemon start
$ ros2 daemon status
$ ros2 daemon stop
Doctor —---------------------------------------
Checks all aspects of ROS 2, and
warns about possible errors and
reasons for issues.
Command
ros2 doctor <arguments>
Arguments
--report: print all warnings
-rf: print reports of failed checks only
-iw: include warnings as failed
checks. Warnings are ignored by
default
Examples
$ ros2 doctor
$ ros2 doctor --report
$ ros2 doctor --include-warnings
Extension Points—----------------------—-
Lists extension points.
Command
ros2 extension_points
<arguments>
Arguments
--all, -a: show extension points which
failed to be imported
--verbose, -v: show more
information for each extension point
Examples
$ ros2 extension_points
$ ros2 extension_points --all
Extension—------------------------------------
Lists extensions of a package.
Command
ros2 extensions <arguments>
Arguments
-a: show extensions which failed to
load or are incompatible
-v: show more information for each
extension
Examples
$ ros2 extensions
$ ros2 extensions --all
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4. ROS 2 Commands Cheat Sheet
Interface—-------------------------------------
ROS applications typically communicate
through interfaces of one of three types:
messages, services, and actions.
Command
ros2 interface [verb]
Verbs
list: list all interface types available
package <package_name>: output
a list of available interface types
within one package
packages: output a list of packages
that provide interfaces
show <interface_type>: output the
interface definition
Examples
$ ros2 interface list
$ ros2 interface package turtlesim
$ ros2 interface show
turtlesim/msg/Pose
$ ros2 interface packages
Launch File—---------------------------------
Allows to execute multiple nodes with
their own complete configuration
(remapping, parameters, etc.) in a
single file, that can launch with only one
command line.
Command
ros2 launch [package_name]
[launch_file_name] <arguments>
Argument
-n, --noninteractive: run the launch
system non-interactively, with no
terminal associated
-d, --debug: put the launch system in
debug mode, provides more verbose
output.
-p, --print, --print-description: print
the launch description to the console
without launching it.
-s, --show-args,
--show-arguments: show arguments
that may be given to the launch file.
--show-all-subprocesses-output,
-a: show all launched subprocesses
output by overriding their output
configuration using the
OVERRIDE_LAUNCH_PROCESS_
OUTPUT envvar.
--launch-prefix LAUNCH_PREFIX:
prefix command, which should go
before all executables. It must be
wrapped in quotes if it contains
spaces (e.g. --launch-prefix 'xterm -e
gdb -ex run --args').
--launch-prefix-filter
LAUNCH_PREFIX_FILTER: regex
pattern for filtering which executables
the --launch-prefix is applied to by
matching the executable name.
Examples
$ ros2 launch
my_first_launch_file.launch.py
$ ros2 launch
my_first_launch_file.launch.py
--noninteractive
$ ros2 launch
my_first_launch_file.launch.py
--show-all-subprocesses-output
Lifecycle—-------------------------------------
Manages node containing a state
machine with a set of predefined states.
These states can be changed by
invoking a transition id which indicates
the succeeding consecutive state.
Command
ros2 lifecycle [verb]
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5. ROS 2 Commands Cheat Sheet
Verbs
list <node_name>: output a list of
available transitions
get: get lifecycle state for one or
more nodes
nodes: output a list of nodes with
lifecycle
set: trigger lifecycle state transition
Examples
$ ros2 lifecycle list
$ ros2 lifecycle get
Multicast—-------------------------------------
In order to communicate successfully
via DDS, the used network interface
has to be multicast enabled.
Command
ros2 multicast [verb]
Verbs
receive: receive a single UDP
multicast packet
send: send a single UDP multicast
packet
Examples
$ ros2 multicast receive
$ ros2 multicast send
Node—------------------------------------------
An executable within a ROS 2 package
that performs computation and uses
client libraries to communicate with
other nodes
Command
ros2 run [package_name]
[executable_name] <arguments>
Arguments
--prefix PREFIX: prefix command,
before the executable. Must be
wrapped in quotes if it contains
spaces
–ros-args: pass arguments while
executing a node
–remap: rename topics name while
executing node
Examples
$ ros2 run turtlesim turtlesim_node
$ ros2 run turtlesim turtlesim_node
--ros-args --remap
__node:=my_turtle
Command
ros2 node [command]
Verbs
list: gives the names of all running
nodes
info <node_name>: access more
information about a node
Examples
$ ros2 node info /my_turtle
Package—--------------------------------------
An organisational unit for ROS 2 code
and promote software reuse.
Create ROS2 package
$ cd <workspace_name>/src
Python package
$ ros2 pkg create –build-type
ament_python [package_name]
C++ package
$ ros2 pkg create –build-type
ament_cmake [package_name]
Parameter—-----------------------------------
A list of configuration values attached to
a node.
Command
ros2 param [verb] <arguments>
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6. ROS 2 Commands Cheat Sheet
Verbs
param list: see the parameters
belonging to nodes
param get <node_name>
<parameter_name>: display the
type and current value of a
parameter
param set <node_name>
<parameter_name> <value>:
change a parameter’s value at
runtime
ros2 param dump <node_name>:
view a node’s current parameter
values
ros2 param load <node_name>
<parameter_file>: load parameters
from a file to a currently running node
Arguments
--output-dir: the absolute path to
save the generated parameters file
Examples
$ ros2 param list
$ ros2 param get /turtlesim
background_g
$ ros2 param set /turtlesim
background_r 150
$ ros2 param dump /turtlesim >
turtlesim.yaml
$ ros2 param load /turtlesim
turtlesim.yaml
rqt tools—----------------------------------—-
The rqt tools allow graphical
representations of ROS nodes, topics,
messages, and other information.
Command
rqt_graph: view the nodes and
topics that are active
rqt: brings up a display screen,
drop-down menu items to visualize
various sources of data
Security—--------------------------------------
The sros2 package provides the tools
and instructions to use ROS 2 on top of
DDS-Security.
Command
ros2 security [verb]
Verbs
create_enclave: create enclave
create_keystore: create keystore
create_permission: create
permission
generate_artifacts: generate keys
and permission files from a list of
identities and policy files
generate_policy: generate XML
policy file from ROS graph data
list_enclaves: list enclaves in
keystore
Examples
$ ros2 security create_keystore
demo_keystore
$ ros2 security create_enclave
demo_keystore /talker_listener/talker
$ ros2 security create_enclave
demo_keystore
/talker_listener/listener
Service—---------------------------------------
Communication-based on a
call-and-response model, services only
provide data when they are specifically
called by a client.
Command
ros2 service [verb] <arguments>
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7. ROS 2 Commands Cheat Sheet
Verbs
list: return a list of all the services
currently active in the system
type <service_name>: find out the
type of a service
find <type_name>: to find all the
services of a specific type
call <service_name>
<service_type> <arguments>: call
a service
Arguments
-r: repeat the call at a specific rate in
Hz
Examples
$ ros2 service list
$ ros2 service find
std_srvs/srv/Empty
$ ros2 service call /spawn
turtlesim/srv/Spawn "{x: 2, y: 2, theta:
0.2, name: ''}"
$ ros2 interface show
turtlesim/srv/Spawn
Topic—------------------------------------------
Element of the ROS graph that acts as
a bus for nodes to exchange messages.
Command
ros2 topic [verb] <arguments>
Verbs
list: return a list of all the topics
info <topic_name>: access more
information about topics
echo <topic_name>: see the data
being published on a topic
pub <--once> <topic_name>
<msg_type> '<args>': publish data
onto a topic directly from the
command line
Arguments
-r: publishing rate in Hz (default: 1)
-p: only print every N-th published
message
-1, --once: publish one message and
exit
-t: publish this number of times and
exit
--keep-alive: keep publishing node
alive for N seconds after the last msg
Examples
$ ros2 topic info /turtle1/cmd_vel
$ ros2 topic echo /turtle1/cmd_vel
$ ros2 topic pub --once
/turtle1/cmd_vel
geometry_msgs/msg/Twist "{linear:
{x: 2.0, y: 0.0, z: 0.0}, angular: {x: 0.0,
y: 0.0, z: 1.8}}"
$ ros2 topic hz /turtle1/pose
Workspace—----------------------------------
Directory containing ROS 2 packages.
Create a ROS 2 workspace directory
$ mkdir -p <workspace_name>/src
Build & Source workspace
$ cd <workspace_name>
$ colcon build
$ source install/setup.bash
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8. ROS 2 Commands Cheat Sheet
Colcon Tools—-------------------------------
colcon is a command line tool to
improve the workflow of building, testing
and using multiple software packages.
Every colcon command starts with the
colcon keyword, followed by a verb and
possible arguments.
colcon [verb] <argument>
For Help on colcon CLI commands-
$ colcon --help
$ colcon [verb] -h
colcon build—---------------------------—
Build a set of packages.
Command
colcon build <arguments>
Arguments
--build-base BUILD_BASE: base
path for all build directories
--install-base INSTALL_BASE:
base path for all install prefixes
--merge-install: install prefix for all
packages instead of a
package-specific subdirectory in the
install base
--symlink-install: use symlinks
instead of copying files from the
source
--test-result-base
TEST_RESULT_BASE: base path
for all test results
--continue-on-error: continue
building other packages when a
package fails to build
--executor sequential: process one
package at a time
–executor parallel: process multiple
jobs in parallel
--packages-select PKG_NAME:
select the packages with the passed
names
--packages-skip PKG_NAME: skip
the packages with the passed names
--parallel-workers NUMBER:
maximum number of jobs to process
in parallel. The default value is the
number of logical CPU cores
Examples
$ colcon build
$ colcon build –build-base build
$ colcon build –install-base install
$ colcon build –merge-install
$ colcon build --symlink-install
$ colcon build --executor sequential
$ colcon build --packages-select
my_pkg
$ colcon build --parallel-workers 5
colcon graph----------------------------------
Generates a visual representation of the
package dependency graph.
Command
colcon graph <arguments>
Arguments
–density: output the density of the
dependency graph
--legend: output a legend for the
dependency graph
--dot: output topological graph in
DOT (graph description language)
--dot-cluster: cluster packages by
their file system path
Examples
$ colcon graph --density
$ colcon graph --legend
$ colcon graph --dot
$ colcon graph --dot-cluster
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9. ROS 2 Commands Cheat Sheet
colcon info---------------------------------—
Shows detailed information about
packages.
Command
colcon info <arguments>
Arguments
PKG_NAME: explicit package
names to only show their information
--base-paths: the base paths to
recursively crawl for packages
--paths: the paths to check for a
package
--packages-select: only process a
subset of packages
--packages-skip: skip a set of
packages
Examples
$ colcon info
$ colcon info --paths ros2_ws/src/*
$ colcon info --packages-select
my_pkg
$ $ colcon info --base-paths
pkg_dir_name
colcon list—--------------------------------—
Enumerates a set of packages.
Command
colcon list <arguments>
Arguments
--topological-order, -t: order output
based on topological ordering
--names-only, -n: output only the
name of each package but not the
path and type
--paths-only, -p: output only the path
of each package but not the name
and type
Examples
$ colcon list --topological-order
$ colcon list --names-only
$ colcon list --paths-only
colcon test—----------------------------------
Runs the tests for a set of packages.
Command
colcon test <arguments>
Arguments
--build-base BUILD_BASE: base
path for all build directories
--install-base INSTALL_BASE:
base path for all install prefixes
--merge-install: install prefix for all
packages instead of a
package-specific subdirectory in the
install base
--test-result-base
TEST_RESULT_BASE: base path
for all test results
--retest-until-fail N: rerun tests up to
N times if they pass.
--retest-until-pass N: rerun failing
tests up to N times.
--abort-on-error: abort after the first
package with any errors.
--return-code-on-test-failure: use a
non-zero return code to indicate any
test failure.
Examples
$ colcon test --test-result-base
./build-test
$ colcon test --retest-until-fail 5
$ colcon test --abort-on-error
$ colcon test
--return-code-on-test-failure
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10. ROS 2 Commands Cheat Sheet
colcon test-result-------------------------—
Summarises the results of previously
run tests.
Command
colcon test-result <arguments>
Arguments
--test-result-base
TEST_RESULT_BASE: base path
for all test results
--all: show all test result files
including the ones without
errors/failures.
--verbose: show additional
information for each error/failure.
--result-files-only: print only the
paths of the result files.
--delete: delete all result files.
--delete-yes: same as –delete
without an interactive confirmation.
Examples
$ colcon test-result --test-result-base
./build-test
$ colcon test-result -all
$ colcon test-result --result-files-only
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